This invention relates to a magnetic head apparatus which is used to record and reproduce signals to and from a rotating magnetic recording medium such as a magnetic disk, and more particularly to a combination magnetic transducer head apparatus which can easily achieve initial formatting of data tracks.
When data signals are to be recorded to or reproduced from a rotating magnetic recording medium such as, for example, a hard disk, it is necessary, particularly upon recording, to form tracks of a regular pitch on the rotating magnetic recording medium. Accordingly, in a conventional apparatus wherein a large number of hard disks are arranged for rotation in an integral relationship, tracking signals are prerecorded in an equal pitch on one of the hard disks so that while the tracking signals are referred to, positions in radial directions of magnetic heads for recording data signals to the other hard disks are controlled to record data signals to any of the hard disks. Such an apparatus has no problems where a large number of hard disks are rotated in an integral relationship, but where data signals are recorded to or reproduced from one or two hard disks, it is not suitable from a point of view of space and cost because it requires an additional hard disk for tracking signals.
Also, in order to record data signals on each hard disk so as to form tracks which have regularly arranged pitches, an apparatus is proposed which records position signals in the form of dots at positions in a radial direction at which individual tracks are to be formed. Since the apparatus only records position signals in the form of dots at positions in a radial direction at which individual tracks are to be formed, it is difficult to record regularly pitched tracks over an entire circumference of a hard disk.
However, in such conventional apparatus, a specific initial formatting system is required, which leads to a drawback that factory equipment become expensive.
Besides, if a magnetic disk is initialized on an initial formatting system other than a magnetic disk device, it may yield an eccentric motion relative to a spindle when it is mounted as a product on a magnetic disk system. This may cause a deterioration in accuracy of a positioning servo mechanism.